In the production of DRI, it would be advantageous to utilize the hot synthesis gas (syngas) from a petroleum refinery bottoms or petroleum coke gasifier as a reducing gas. However, this is typically not feasible as the syngas must be cooled to <200 C to enable use of conventional technology for removing sulfur and dust, resulting in significant equipment costs and energy inefficiency.
Thus, in various exemplary embodiments, the present invention provides methods and systems for producing DRI utilizing a petroleum refinery bottoms or petroleum coke gasifier and a hot gas cleaner. Cooling of the hot synthesis gas to <200 C is not necessary. Rather, the syngas from the petroleum refinery bottoms or petroleum coke gasifier is desulfurized and dedusted at high temperature (>350 C) using a hot gas cleaner, well known to those of ordinary skill in the art, although not in such an application. This hot gas cleaner may be high pressure or low pressure.